Sri Sulandari

Deteksi dan Kajian Kisaran Inang Virus Penyebab Penyakit Daun Keriting Kuning Cabai

High incidence of Pepper yellow leaf curl virus (PepYLCV) was observed in Indonesia since early 2000. Disease incidence in Yogyakarta, Central and West Java reached 100% on Capsicum frutescens, but only 10-35% on C. annuum. As an exception, the disease incidence on C. annuum cv. TM 999 was in the range of 70-100%. The causal agent of the disease, PepYLCV, was detected by polymerase chain reaction. Viral specific DNA fragment of the size ~1600 bp and ~550 bp was amplified from infected plants using two pairs of geminivirus universal primers pAL1v1978/pAL1c715, and pAv494/pAc1048, respectively. The PepYLCV has an intermediate host range including plants belonging to the family of Solanaceae, Leguminosae, and Compositae. The species belonging to the families of Cucurbitaceae, Malvaceae, Chenopodiaceae, and Amaranthaceae were resistant to the virus. Physalis floridana, is very prospective as a propagation host for the geminivirus infecting pepper. Nicotiana spp., cucumber, watermelon, cotton, and Sida sp. could be used as a differential host. Besides, Capsicum frutescens cv. Cakra, tomato, N. benthamiana, N. glutinosa, and Ageratum conyzoides could be used as indicator plants for the geminivirus infecting pepper.

Molecular Evidence for Mixed Infections of Four Begomoviruses in Common Bean and Yard Long Bean Showing Severe Yellow Symptoms in East Java, Indonesia

The genus Begomovirus (family Geminiviridae) is transmitted by whitefly (Bemesia tabaci) in a persistent manner and causes yellowing disease symptoms with significant losses of leguminous crops in Indonesia. Mixed infection with Begomovirus was detected using a polymerase chain reaction assay using four pairs of specific primers: AC2-F/AC2-R, TYLCV-F/TYLCV-R, TLCV-CPI/TLCV-CPT, and PepYLCV-F/PepYLCV-R, amplifying the targeted DNA fragments of ~504 bp, ~1668 bp, ~700 bp, and ~850 bp, respectively. Samples were collected from different geographic areas in East Java (Kencong and Pujon), which represented the difference in altitudes. Molecular evidence indicated that the Tomato yellow leaf curl virus (TYLCV), Tomato leaf curl virus (ToLCV), Pepper yellow leaf curl virus (PepYLCV), and Mungbean yellow mosaic virus (MYMV) co-infected common bean plants showing mosaic symptoms, cupping, leaf malformations, yellowing, and stunting. ToLCV, PepYLCV, and MYMV were found in mixed infections of yard long bean with mosaic and yellowing symptoms. Common bean and yard long bean only infected by ToLCV or PepYLCV showed mosaic symptoms. Symptoms of yellow disease in infected common bean and yard long bean in the Kencong area showed more complexes than those in Pujon.